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941.
Haruhiro Muratsubaki Akiko Yamaki 《Indian journal of clinical biochemistry : IJCB》2011,26(4):416-419
The effect of acute hypoxic hypoxia on the profile of plasma amino acids in rats was studied and compared to that resulting
from acute liver injury induced by giving carbon tetrachloride. In hypoxic rats exposed to 45% air in N2 for 5 h, the concentrations of branched chain amino acids, including valine, leucine and isoleucine, and aromatic amino acids
such as phenylalanine and tyrosine were significantly increased as compared to those in normoxic rats. The ratio of branched-chain
to aromatic amino acids (Fischer’s ratio) was significantly decreased. The levels of arginine and citrulline, which are related
to the urea cycle, were also depressed. Furthermore, plasma proline level was reduced in hypoxic rats. The activities of plasma
marker enzymes for tissue damage remained unchanged during hypoxia, indicating that tissue injury was not induced by exposure
to hypoxic conditions. We suggest that the characteristic profile of plasma amino acids and the Fischer ratio are valuable
tools for understanding the pathology of acute hypoxia in the absence of systemic tissue damage. 相似文献
942.
943.
Khan S Bhargava A Pathak N Maudar KK Varshney S Mishra PK 《Indian journal of clinical biochemistry : IJCB》2011,26(2):161-168
The present study evaluated the plausible role of circulating biomarkers in immune pathogenesis of chronic hepatitis considered
a priority in clinical hepatology. Total viral load of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) patients
was quantified and correlation studies were performed with circulating levels of Th1/Th2 cytokines; C reactive protein and
circulating nucleosomes; glutathione reductase (GR) and superoxide dismutase. To our knowledge, the study is first among its
kind that validates strong positive correlation of viral load with IL-4, IL-6, GR in HBV and IL-6, IL-10, GR in HCV infections.
Although, multi-centric studies including large cohorts are required for translating our findings to clinical practice, however,
role of these biomarkers with potential diagnostic or prognostic significance might be helpful in clinical assessment of high-risk
individuals, thereby, designing interventional strategies, towards development of personalized medicare. The results of our
study also offer valuable insights of immune signaling mediators engaged in development of hepatocellular carcinoma. 相似文献
944.
945.
Nitric oxide (NO) a free radical having both cytoprotective as well as tumor promoting agent is formed from l-arginine by converting it to l-citrulline via nitric oxide synthase enzymes. The reaction product of nitric oxide with superoxide generates potent oxidizing
agent, peroxynitrite which is the main mediator of tissue and cellular injury. Peroxynitrite is reactive towards many biomolecules
which includes amino acids, nucleic acid bases; metal containing compounds, etc. NO metabolites may play a key role in mediating
many of the genotoxic/carcinogenic effects as DNA damage, protein or lipid modification, etc. The basic reactions of nitric
oxide can be divided as direct effect of the radical where it alone plays a role in either damaging or protecting the cell
milieu and an indirect effect in which the byproducts of nitric oxide formed by convergence of two independent radical generating
pathways play the role in biological reactions which mainly involve oxidative and nitrosative stress. Nitric oxide is also
capable of directly interacting with mitochondria through inhibition of respiration or by permeability transition. Reaction
of nitric oxide with metal ions include its direct interaction with the metals or with oxo complexes thereby reducing them
to lower valent state. Excessive production of nitric oxide can be studied by inhibiting the synthetic pathway of nitric oxide
using both selective or specific nitric oxide synthase inhibitor or non-selective nitric oxide synthase inhibitor with respect
to isoforms of nitric oxide. 相似文献
946.
Franky D. Shah Rasheedunnisa Begum Bhairavi N. Vajaria Kinjal R. Patel Jayendra B. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of clinical biochemistry : IJCB》2011,26(4):326-334
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world.
Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce
the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to
be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers,
oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement
of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived
from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative
to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post
therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches
to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of
oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to
combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer. 相似文献
947.
948.
Bart Van Looy Paolo LandoniJulie Callaert Bruno van PottelsbergheEleftherios Sapsalis Koenraad Debackere 《Research Policy》2011,40(4):553-564
The phenomenon of entrepreneurial universities has received considerable attention over the last decades. An entrepreneurial orientation by academia might put regions and nations in an advantageous position in emerging knowledge-intensive fields of economic activity. At the same time, such entrepreneurial orientation requires reconciliation with the scientific missions of academia. Large-scale empirical research on antecedents of the entrepreneurial effectiveness of universities is scarce. This contribution examines the extent to which scientific productivity affect entrepreneurial effectiveness, taking into account the size of universities and the presence of disciplines, as well as the R&D intensity of the regional business environment (BERD). In addition, we assess the occurrence of trade-offs between different transfer mechanisms (contract research, patenting and spin off activity). The data used pertain to 105 European universities. Our findings reveal that scientific productivity is positively associated with entrepreneurial effectiveness. Trade-offs between transfer mechanisms do not reveal themselves; on the contrary, contract research and spin off activities tend to facilitate each other. Limitations and implications for future research are discussed. 相似文献
949.
Lidwien van de WijngaertAuthor Vitae Willem PietersonAuthor Vitae Marije L. TeerlingAuthor Vitae 《International Journal of Information Management》2011,31(5):415-419
Information technology allows national and local governments to satisfy the needs of citizens in a cost effective way. Unfortunately, citizens still tend to prefer traditional, more costly channels, such as the front desk, phone and mail. Through pilot projects government agencies attempt to influence this behavior of citizens, directing them towards the online channel. With this paper we provide insight into the possibility to influence citizens’ behavior in the complex landscape of multi-channel service provision. The paper systematically compares five pilot projects using a framework that is based on organizational and marketing literature. The results show that socio-psychological factors are crucial in multi-channel management, much more than the technology itself. We conclude that citizens can be directed towards the online channel. However, not all projects are successful. Economic and legal instruments tend to sort more direct effects than communication or service instruments. Moreover, organizational factors such as bureaucracy often hinder eventual success. Choosing a smart and relatively small scope and strong project manager may help to evoke success in directing citizen online behavior. 相似文献
950.
Thomas Gould 《Publishing Research Quarterly》2011,27(1):36-53
Perhaps nothing strikes more fear into the hearts of all tenure-track professors than the process itself. Are four papers in this journal good enough? Are eight papers in another okay? What if someone doesn’t like me or my area of research? These issues have plagued academia since the first essay was penned by the first researcher hundreds of years ago. While personal bias and journal preference continue to infect honest tenure reviews, solutions exist. This does not mean we have a magic bullet to solve issues of bullying or elitism. However, if we are honest in our desire to improve the Academy, we should avail ourselves of every possible tool for improvement. This essay is based on a survey sent to 2,500 mass communication educators. Of the almost 500 respondents, roughly 10% took the time to express emotions that ranged from fear and confusion to outright rage and anger, all because what ought to be clear is not. The author offers 10 ideas of how academia can improve its evaluation of new faculty, as well as a few suggestions regarding the unnecessary inclusion of personal issues in a process that ought to be about creating better researchers and teachers. 相似文献